Installing a lake monitoring buoy on Lake Hayes
Lake Hayes will be the first lake in Otago to have a monitoring buoy installed.
Installation is scheduled prior to the summer 18/19 season.
What is a lake monitoring buoy?
A lake monitoring buoy is an autonomous, solar-powered water quality monitoring system.
It has two parts:
1. A weather station mounted above the water
2. A water quality sensor package, which uses an electric winch and armoured data cable to raise and lower the sensors throughout the water column
What do lake buoys measure?
1. The top mounted weather station measures data related to climate and weather, including:
- wind speed and direction
- air temperature
- solar radiation
- relative humidity
- barometric pressure
2. The winch-operated sensors move up and down the water column collating data related to water quality, including:
- Water temperature
- Dissolved oxygen
- Chlorophyll fluorescence
- Phycocyanin fluorescence
- Turbidity (to detect sediment)
Here is a schematic diagram of how the various components of a typical lake monitoring buoy work.
Why is monitoring important for Lake Hayes?
It helps us track changes in water quality. These changes can vary from seasons to minutes. Monthly or seasonal monitoring is not usually sensitive enough to detect these changes.
Data will be collected every 15 minutes. This high-frequency data will enable Otago Regional Council scientists to better understand processes that affect the health of Lake Hayes.
Soon we will have very accurate data on temperature and formation of thermal layers (stratisfication), oxygen depletion (especially from water near the bottom), algal species, sediment and water clarity.
This data will greatly improve our understanding of how Lake Hayes is responding to the environment in both the short and long-term. This detailed data and will give us a clearer picture of what is happening in the lake - so we can make better decisions about remediation.